One way to start saving money and lower your gas consumption and carbon footprint is by hypermiling. I recently learned this driving technique through Super Commuter Driving Instruction of North Andover.

"Anyone can learn to hypermile and save money, gas and the environment. It's safe and it's free," Matt Herring of Super Commuter said.

For a nominal fee, Herring teaches commuters how to drive more efficiently with the cars they have. When he offered instruction in my 2007 Hyundai Sonata, he told me about his experience with his 2005 Toyota 4Runner. Last year, Herring improved his gas usage from 17 to 22 miles per gallon, gaining five miles per gallon and saving 3 gallons every time he filled up his tank.

In one year, driving 15,000 miles, he reports he saved 150 gallons of gasoline and about $900.

To obtain accurate figures, Herring fills up at the same gas station using the same pump and tracks his savings using a scan gauge — an electronic device costing $140 to $160 that provides data on 13 factors, including how much a ride costs "down to the penny" and how to find your vehicle's ideal ignition time (IGM). He also introduced me to an online fuel log tool available on Ecomodder.com, which he recommended as a hypermile resource.

The pre-drive inspection

During the hypermile run-up, Herring went over fueleconomy.gov ratings for my car, with a carbon footprint of 7.7, "which is lower than average," he said. My Hyundai also averages 382 miles per tank. He then measured my tire pressure, and we discussed grill blocks and engine heaters before hitting the road for a practical on efficient driving techniques.

Tire pressure is recommended at 32 psi for my tire size. Herring recommended increasing to about 44 psi, assuring me that tire wear and blowout risk would be no higher. The cons might be a bumpier ride, but on the plus side I would increase my miles per gallon by about 5 percent. Herring cautioned me to lower the tire pressure in winter because higher psi reduces traction.

Engine grill blocks make any car more aerodynamic and allow the engine to heat up faster in winter. Warm engines are more efficient, so gas-guzzling cold starts can be minimized with these. Inexpensive foam pipe insulation kits are available from hardware stores or coroplast from old election signs can be used to construct grill blocks.

For $15 to $50, engine block heaters can be used to preheat car engines in winter to combat cold-start fuel consumption. Herring said the electricity required is equivalent to leaving a conventional light bulb on for two hours a day for six months — but using a heater daily for six months added 50 extra miles per tank in his Toyota 4Runner.

A primer on hypermiling

The practice involves:

Driving with a lighter foot and a steeper angle so as not increase engine rpm, which increases gas consumption.

Taking the time and appropriate precautions to accelerate slowly, as opposed to revving the engine.

Getting to know commute routes in order to time lights, taking the foot off the gas pedal and avoiding the break as long as possible, which often results in a coast through a lighted intersection.

Learning to coast (foot off gas and break) as much as possible, rather than making frequent starts and stops, which can get you through a traffic light, a temporary slow-up, or a stop caused by turning traffic up ahead.

Training to Pulse and Glide (P&G). P&G requires a moderate pulse on the gas pedal to reach a designated speed (say 60 mph in a 55 mph) and then with foot off the pedal, gliding down to 50 mph. "Repeat the P&G as many times as your commute allows to minimize the time you are using the gas pedal and maximize the time you are on a gas-free coast," Herring advised. In this manner, a commuter uses less gas to maintain the speed limit along their daily route.

For the advanced, although it's controversial even among die-hard hypermilers, a shift into neutral on the glide part of P&G will, according to Herring, "eliminate natural engine braking that occurs, giving ... a longer glide." In some states, hypermiling is illegal, Herring noted.

My test drive

I drove from Cabot Street in Beverly to Route 128 and to my market on Route 114. The scan gauge recorded that my seven-mile trip came in at 26.4 mpg using 0.27 gallons of gas. I averaged 23 mph with a max speed of 57 mph.

Herring's 7.1-mile return trip following the same route came in at 34.5 mpg but used only 0.21 gallons of gas. He averaged 25 mph with a max speed of 55 mph.

According to the scan gauge, Herring's trip also cost 15 cents less than mine.

The bottom line is that by applying hypermiling techniques, he drove faster and more efficiently — saving money and reducing gas consumption, and ergo, carbon loading to the atmosphere, on my seven-mile trip.

I had revved the engine a bit when changing lanes in a heavily trafficked, lighted intersection — having failed to anticipate the slowdown and some turning traffic. This single everyday driving maneuver costs both gas and pennies.

Herring had coasted through more lights than I had, he also mastered P&G and maintained my car's IGM, which the scan gauge calculated was around 47 to 49 mph and 1,900 rpm. He also didn't change lanes the entire route back to Beverly and shifted to neutral on each hill he glided down on Route 128 north.

The results

Since my lesson, I decided to inflate my car's tires to 40 psi for the summer. It's under Herring's suggestion, but over the manufacturer's recommended number. I am driving slower and maintaining my IGN at 48 mph whenever possible (which is often, because I don't have a commute, and I schedule meetings and errands before or after the morning and evening rush hours).

I am learning to P&G, but it definitely takes practice to adjust to coasting, as opposed to hard driving. I have not shifted to neutral in my glides — yet!

Even so, my Hyundai Sonata drove 500 miles on the one tank since my lesson, compared to the 382 it's rated at! I am going to recycle election signs the next voting day and fashion some swanky grill blocks for my pearl white Sonata, and I'm considering an engine block heater. If I can achieve 600 miles per tank, I'll be thrilled.

On a final note, Herring, who commutes from North Andover to Danvers every day, recently purchased a 2009 Toyota Prius and reports that he is attaining 63 miles per gallon for each tank of gas — well over the rated 47 miles per gallon. In just two months, Herring's Prius has saved him $200. In its first year, he expects to save more than 250 gallons of fuel and more than $1,000.

Next week's Green Quick Fixes will look at low-carbon-footprint vehicle options in the marketplace.

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Andrea Fox, a Beverly resident, has been writing about environmental sustainability and eco-topics for nine years. She is a member of the Society of Environmental Journalists and a watershed protection advocate in Salem Sound Watershed.